Dictionary-based order-preserving string compression for main memory column stores

Abstract

Column-oriented database systems [19, 23] perform better than traditional row-oriented database systems on analytical workloads such as those found in decision support and business intelligence applications. Moreover, recent work [1, 24] has shown that lightweight compression schemes significantly improve the query processing performance of these systems. One such a lightweight compression scheme is to use a dictionary in order to replace long (variable-length) values of a certain domain with shorter (fixedlength) integer codes. In order to further improve expensive query operations such as sorting and searching, column-stores often use order-preserving compression schemes.